Why are all reference sensitivity requirement of all bands different in WCDMA (UMTS)

As shown above, the reference sensitivity requirement:

B1: -106.7
B2: -104.7
B3: -103.7
B4: -106.7
B5: -104.7


They are different.



However, from the sensitivity formula,

These parameters, such as bandwidth, SNRmin, are all the same in these bands.

In theory, the reference sensitivity requirement should be identical.


What makes them different?



Thanks a lot~!

The basic noise power density (kTB) of a WCDMA receiver is -108 dBm/3.84 MHz, at 290K (17°C).

The 3GPP spec set various reference sensitivities in different bands function of potential interferers (in-band and out-of-band) which could appear in those bands.

Thanks for your reply.